A milking parlor generally includes an array of individual milking stalls, each milking stall being designed to hold a cow or other dairy animal while being milked. Typically, an operator or milking robot is required to perform such tasks as insuring that the animals are properly situated in the milking stalls, washing the udder prior to milking, applying milking units; monitoring and attending to operation of the milking units.
Generally, there are two principle ways to milk cows. One method is to bring the milking equipment to the cows while the cow is retained in a, often described as around the barn pipeline, or pipeline, tie-stall, and stantion barn. The alternative method of milking cows is to bring the cows to the milking equipment. This arrangement is known as free-stall or milking parlor. There are several ways to configure the milking system.
Pipeline Milking System
In the pipeline milking system, each cow is confined to its own stall or stanchion (headlock device). In the stall, the cow is fed, watered and can lay down. The cow is restrained to the stall by tying (tie-stall) or stanchion.
A milk line is routed over the stalls along with a pulsator line and any electrical lines needed to operate corresponding milking units. Routing the milk line over the stalls is referred to as a high line. The milk line routes the milk to a milk room by gravity where the milk is pumped into a bulk tank. Ports or stall cocks are located between the stalls to which individual milking units connect.
In operation, the operator takes the milking unit to the stall and operably connects the milking unit to the stall cock. The milking unit is then applied to the cow.
When the cow has been milked out, the operator removes the unit and applies it to the next cow, moving the unit from stall cock to stall cock as the process moves throughout the barn.
As with any system, there are efficiency benefits and drawbacks to the pipeline milking system. One benefit is that the system allows the operator to prepare the next cow for milking while the previous cow is being milked. When the first cow is finished milking, the unit can be immediately moved to the prepared next cow. However, the pipeline system induces significant operator fatigue. The milking process requires the operator to bend over or squat down to access the udder for preparing, milking and post dipping. There is also considerable freedom for the cow to move around within the stall, which results in milking units being kicked off or stepped on. Immediate attention is required by the operator upon a milking unit being kicked off or stepped on. Further, there is little to protect the operator from being kicked or stepped on. As each stall requires a corresponding stall cock, a large number of stall cocks are employed and any percentage of failure or leakage results in required maintenance. Further, some portions of the milk line may be soiled by milk and not cleaned for hours, as the milking process has moved to another part of the barn. Also, the relatively long pipe lengths cause hot washing water to cool very quickly. In addition, once the milk has been extracted from the cow, it must be lifted to the pipeline running above the stall. Typically, this elevating process is done with the same vacuum used to extract the milk. Thus, a stable vacuum at the cow teats is very difficult to achieve. Although automation devices such as milk meters and automatic take offs have inherent individual benefits, it is difficult to implement these devices as they must be carried from cow to cow and secured to each stall.
Parlor Milking System
In the parlor milking system, each cow has a stall where it can lay down, however, the cows are not restrained to the stall and may move about the barn (free stall). For milking, the cows are gathered and taken to the milking parlor. Fences or gates form the milking stalls of the milking parlor and control the flow and position of the cows in the parlor. The fences and gates also serve to protect the operator from getting kicked or stepped on. Typically, the milking stalls are considerably smaller than those found in free stalls or tie stalls, as it is not intended that the cows lay down in the milking stall. This closer confinement reduces freedom of movement of the cow and results in less kick off of the milking unit. As the milking equipment is not manually moved from cow to cow, automatic take offs and milk meters can be permanently mounted and utilized efficiently in the milking parlor system.
Herringbone Milking Parlor—Batch Operation
The herringbone-milking parlor includes two rows of milking stalls separated by an operator pit. The milking stalls arrange the cows for milking from the side. The cows enter the milking parlor in a single file and turn at an angle away from the operator pit. The cows overlap each other and thus form a herringbone pattern. The operator works from the pit, which is a lowered area between the opposing rows of milking stalls. In the lowered operator pit, the operator is able to stand upright and attend to the cows without having to bend or squat down. The milk line is located along a side of the operator pit or in a basement below the parlor floor and is lower than the cow udder. This configuration provides for more stable vacuum at the teats, as the milk is not lifted by vacuum. Locating the milk line lower than the cow's udder is referred to as a low line system. However, as this herringbone parlor is a batch processing, when the first cow is finished milking it must wait until all the cows in the batch are finished before the cow can leave. Therefore, inefficiencies are encountered as milked cows in a batch cannot be replaced until the last cow in the batch has been processed.
Tandem Parlor—Batch or Single Operation
The tandem parlor also includes two rows of milking stalls separated by an operator pit. The milking stalls are arranged for milking the cows from the side. The cows enter the milking parlor single file and stop without turning away from the operator pit. This configuration requires a much longer milking parlor than other milking parlors having the same capacity. Each milking stall in the tandem parlor is the length of a cow from the next milking stall. Known variations of this arrangement allow each stall to have its own entrance and separate exit gate thereby allowing the operator to release a cow when it is finished and let a new cow into that stall even though the rest of the cows in that side are still milking. Typically, the tandem parlor also employs a low line. Further, the tandem parlor has a long walking distance for both animals and operators.
Parallel Parlor—Batch Operation
A parallel parlor also includes two rows of milking stalls separated by an operator pit. The milking stalls arrange the cows for milking from between the rear legs. The cows enter the parlor in a single file and turn perpendicular to the operator pit in a parallel cow-to-cow orientation. The parallel parlor allows for a very short milking parlor with each milking stall being only a cow's width away from the next milking stall. Further, since the milking is done from between the rear legs, the milking equipment is located where manure would fall upon it. A gutter is required to catch the manure before it can soil the milking equipment. The cows tail can also hinder milking from between the rear legs. Often trimming or docking the tail enhances efficiency of the parallel parlor.
Flat Barn Parlor—Single Operation
The flat barn-milking parlor includes one or two rows of milking stalls with no recessed operator pit or an elevation change in the milking parlor that can be handled by the cow stepping up. It is similar to the pipeline type arrangement, wherein, the operator milks the cows from the side and thus the operator must bend or squat to access the udder. Because there is no recessed operator pit, the cows can enter the milking stalls from the rear of the stall without having to move in a single file. This allows the operator to release a cow from the stall as soon as the cow is finished milking. The next cow may be then introduced into the milking stall from the rear of the milking stall. Some flat barn parlors have small recessed operator pits at each milking station where the operator steps down into the pit and does not have to bend over as far to milk the cow. Typically, these pits are located in between two adjacent milking stalls and do not run the length of the milking parlor and to reach more than two cows, the operator must step up out of one pit and step down into the next pit. Most flat barn parlors use a high line as cow traffic prevents the use of a low line. However, the operator walking distance in a flat barn parlor is longer than other parlor arrangements of equal capacity. That is, the stalls are arranged either in a single row, or the two rows of stalls are far enough apart to allow cow traffic between the rows. The flat barn parlor induces operator fatigue from the long walking distance and the need to either bend or squat to access the udder or climb in and out of individual recessed operator pits.
Rotary Parlor—Single Operation
In an effort to overcome the considerable time for cows to enter and fill the milking parlor in the herringbone and parallel parlor configurations, the rotary parlor is employed. The rotary parlor does not load and release cows in groups as do the herringbone and parallel arrangements. In contrast, the rotary parlor arranges a herringbone, tandem or parallel type stalls around a moving platform. When an empty stall passes the loading gate, a cow forwardly moves into the empty stall. The cow is milked either from the side or between the rear legs, depending upon the milking stall arrangement, as the milking parlor continues to rotate. Prior to reaching the entrance gate, where the cows are introduced, the milked cow is exposed to an exit gate. The speed of the rotation of the parlor is set such that cows requiring the longest time for milking are finished milking before reaching the exit gate.
However, there is no provision for releasing a cow as soon as the cow is finished and replacing the then empty milking stall with a fresh cow.
In most rotary parlors, the operator(s) can not see all of the animals in the parlor. A unit fall off may go undetected until an operator post dips the animal. If the operator detects a condition that requires immediate attention, they must chase the stall to remedy the situation.
The rotary parlor prevents the operator from having to wait for groups of cows to load into the parlor, but cows having a milking time that is less than the rotation time, must still wait before they can exit the parlor.
The rotary parlor uses a low line. However, the rotation of the rotary parlor requires a multitude of moving parts and enhanced complexity to install and service. For example, service connections to the parlor, including plumbing, vacuum, communications and electrical must be dynamic.
Therefore, a need still remains to enhance the efficiency in milking cows by eliminating idle time for both the operator and the equipment. The need exists for a method of presenting animals to be milked, wherein milking equipment and associated automation devices allow the operators to milk more cows faster than in a conventional milking system. The further need exists for enhancing ergonomic working conditions for operators.